Sensory Receptors and Neural Pathways (6A) Practice Test

A clinic screens patients for peripheral neuropathy using a tuning fork (128 Hz) placed on the big toe. Some patients report they feel the vibration briefly, but it fades quickly compared with age-matched controls, despite normal skin temperature and no visible injury. The clinician suspects impaired function of mechanosensory afferents that normally convey vibration information efficiently to the central nervous system.

Which outcome is most consistent with the neural mechanism discussed?

In an olfaction experiment, participants sniff two solutions while their nasal passages are monitored for airflow. Solution X produces a strong smell at first that diminishes over repeated sniffs, even though airflow and concentration remain constant. Solution Y produces a stable smell across sniffs. The team argues that the pattern reflects receptor-level and early neural adaptation that reduces signaling for unchanging stimuli.

Based on the scenario, which outcome is most consistent with the neural mechanism discussed?